In recent years, use of a transparent plastic film as a substrate instead of a glass sheet has been proposed for displays (e.g., liquid crystal display and electroluminescence (EL) display) in order to implement a reduction in thickness, a reduction in weight, an increase in flexibility, and the like. However, since a plastic film tends to allow steam, oxygen, and the like to pass through as compared with a glass sheet, elements provided in a display may deteriorate.
In order to solve this problem, Patent Document 1 discloses a flexible display substrate in which a transparent gas barrier layer formed of a metal oxide is stacked on a transparent plastic film.
However, since the transparent gas barrier layer formed of a metal oxide is stacked on the surface of the transparent plastic film by vapor deposition, ion plating, sputtering, or the like, cracks may occur in the gas barrier layer when the substrate is rounded or folded, so that the gas barrier capability may deteriorate.
Patent Document 2 discloses a gas barrier laminate that includes a plastic film, and a resin layer that contains a polyorganosilsesquioxane as the main component and is stacked on at least one side of the plastic film.
However, since it is necessary to further stack an inorganic compound layer in order to obtain a gas (e.g., oxygen and steam) barrier capability, the process becomes complicated, and the production cost increases. Moreover, toxic gas may be used.    Patent Document 1: JP-A-2000-338901    Patent Document 2: JP-A-2006-123307